diff --git a/examples/test.c b/examples/test.c
index 8ee735a57f006ca59a8e30fbf07811628e378adb..aaa8ac160c731336144a82ddb86bb932ecacef0a 100644
--- a/examples/test.c
+++ b/examples/test.c
@@ -784,8 +784,8 @@ int main(int argc, char *argv[]) {
/* Initialize the engine with this space. */
tic = getticks();
message("nr_nodes is %i.", nr_nodes);
- engine_init(&e, &s, dt_max, nr_threads, nr_queues, nr_nodes, myrank,
- ENGINE_POLICY | engine_policy_steal);
+ engine_init(&e, &s, dt_max, nr_threads, nr_queues, nr_nodes, myrank ,
+ ENGINE_POLICY | engine_policy_steal | engine_policy_paranoid);
if (myrank == 0)
message("engine_init took %.3f ms.",
((double)(getticks() - tic)) / CPU_TPS * 1000);
diff --git a/src/debug.c b/src/debug.c
index d55d5443457fe3be41f6d1983a1eca8d7ab99f3c..0ebbd44ae03ffc6ddfabab78e577335f0b9bbe5a 100644
--- a/src/debug.c
+++ b/src/debug.c
@@ -20,8 +20,20 @@
#include <stdio.h>
-#include "const.h"
-#include "part.h"
+/* This object's header. */
+#include "debug.h"
+
+/**
+ * @brief Dump the information pertaining to the given cell.
+ */
+
+void print_cell(struct cell *c) {
+ printf(
+ "## Cell 0x%0zx: loc=[%.3e,%.3e,%.3e], h=[%.3e,%.3e,%.3e], depth=%i, "
+ "split=%i, maxdepth=%i.\n",
+ (size_t)c, c->loc[0], c->loc[1], c->loc[2], c->h[0], c->h[1], c->h[2],
+ c->depth, c->split, c->maxdepth);
+}
/**
* @brief Looks for the particle with the given id and prints its information to
diff --git a/src/debug.h b/src/debug.h
index ddd33d527e4f4fde967344a3f4f63ea98df0e37a..42269fc267e6d5721990b992c92c515a5764f6a9 100644
--- a/src/debug.h
+++ b/src/debug.h
@@ -23,7 +23,7 @@
#include "cell.h"
#include "part.h"
-
+void print_cell(struct cell *c);
void printParticle(struct part *parts, long long int i, int N);
void printgParticle(struct gpart *parts, long long int i, int N);
void printParticle_single(struct part *p);
diff --git a/src/engine.c b/src/engine.c
index fcecde15fb70997ca13c8c0f27a210ea7cffffdd..90c0e124143438145349d41db667bc8cabd7a52d 100644
--- a/src/engine.c
+++ b/src/engine.c
@@ -62,6 +62,79 @@
/** The rank of the engine as a global variable (for messages). */
int engine_rank;
+/**
+ * @brief Check if a single particle is OK.
+ *
+ * @return Zero if all checks passed, non-zero otherwise.
+ */
+int engine_check_part(struct part *p) {
+ if (p == NULL || p->mass == 0.0f || p->h == 0.0f) {
+ message("Bad particle data.");
+ printParticle_single(p);
+ return 1;
+ } else if (p->x[0] == 0.0 && p->x[1] == 0.0 && p->x[2] == 0.0) {
+ message("Bad particle location.");
+ printParticle_single(p);
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+/**
+ * @brief Check if a cell's data is reasonable, also check if its particles
+ * are OK.
+ *
+ * @return Zero if all checks passed, non-zero otherwise.
+ */
+
+void engine_check_cell(struct cell *c, void *data) {
+ /* Check the cell data. */
+ if (c->count == 0) {
+ print_cell(c);
+ error("Empty cell.");
+ }
+
+ /* Check the particles. */
+ for (int k = 0; k < c->count; k++) {
+ if (engine_check_part(&c->parts[k])) {
+ print_cell(c);
+ error("Bad particle in cell.");
+ }
+ }
+
+ /* Check that the progeny, if any, contain all the particles. */
+ if (c->split) {
+ int count = 0;
+ for (int k = 0; k < 8; k++) {
+ if (c->progeny[k] != NULL) {
+ count += c->progeny[k]->count;
+ }
+ }
+ if (count != c->count) {
+ print_cell(c);
+ error("Progeny cell counts don't add up.");
+ }
+ }
+}
+
+/**
+ * @brief Runs a series of checks to make sure we have no bad particles.
+ */
+
+void engine_check(struct engine *e) {
+ /* Check all particles directly. */
+ struct space *s = e->s;
+ for (int k = 0; k < s->nr_parts; k++) {
+ if (engine_check_part(&s->parts[k])) {
+ error("Bad particle s->parts[%i], aborting.", k);
+ }
+ }
+
+ /* Check each cell in the space. */
+ space_map_cells_post(s, 1, &engine_check_cell, NULL);
+}
+
/**
* @brief Link a density/force task to a cell.
*
@@ -1720,6 +1793,7 @@ void hassorted(struct cell *c) {
*
* @param e The #engine.
*/
+
void engine_step(struct engine *e) {
int k;
@@ -1733,6 +1807,11 @@ void engine_step(struct engine *e) {
TIMER_TIC2
+ if (e->policy & engine_policy_paranoid) {
+ message("Checking system sanity...");
+ engine_check(e);
+ }
+
/* Get the maximum dt. */
if (e->policy & engine_policy_multistep) {
dt_step = 2.0f * dt;
@@ -1766,6 +1845,11 @@ void engine_step(struct engine *e) {
// printParticle(parts, k);
// printParticle( e->s->parts , 3392063069037 , e->s->nr_parts );
+ if (e->policy & engine_policy_paranoid) {
+ message("Checking system sanity...");
+ engine_check(e);
+ }
+
/* Re-distribute the particles amongst the nodes? */
if ( e->forcerepart )
engine_repartition( e );
@@ -1775,6 +1859,11 @@ void engine_step(struct engine *e) {
engine_check(e);
}
+ if (e->policy & engine_policy_paranoid) {
+ message("Checking system sanity...");
+ engine_check(e);
+ }
+
/* Prepare the space. */
engine_prepare(e);
@@ -1792,6 +1881,11 @@ void engine_step(struct engine *e) {
(1 << task_type_grav_up) | (1 << task_type_grav_down) |
(1 << task_type_link));
+ if (e->policy & engine_policy_paranoid) {
+ message("Checking system sanity...");
+ engine_check(e);
+ }
+
TIMER_TOC(timer_runners);
// engine_single_force( e->s->dim , 8328423931905 , e->s->parts ,
diff --git a/src/engine.h b/src/engine.h
index 65aa028401344f953d7a23a5c83c030278bbdcb7..caa286e7d3c518c0aba84fd9da1b6ff9ef6a78f4 100644
--- a/src/engine.h
+++ b/src/engine.h
@@ -41,6 +41,7 @@
#define engine_policy_cputight 64
#define engine_policy_mpi 128
#define engine_policy_setaffinity 256
+#define engine_policy_paranoid 512
#define engine_queue_scale 1.2
#define engine_maxtaskspercell 128
diff --git a/src/space.c b/src/space.c
index eeb42f328f3a91439110c832fea93798862869a6..157850080b148233168be26789d5be0110dc7938 100644
--- a/src/space.c
+++ b/src/space.c
@@ -844,7 +844,7 @@ static void rec_map_cells_post(struct cell *c, int full,
}
/**
- * @brief Map a function to all particles in a aspace.
+ * @brief Map a function to all particles in a space.
*
* @param s The #space we are working in.
* @param full Map to all cells, including cells with sub-cells.